Roller shutter and improved method of manufacture thereof



F. GRIESSER Sept. 13, 1966 ROLLER SHUTTER AND IMPROVED METHOD OF MANUFACTURE THEREOF Filed March 2, 1964 United States Patent 3,272,256 ROLLER SHUTTER AND IMPROVED METHOD OF MANUFACTURE THEREOF Friedrich Griesser, Aadorf, Thurgau, Switzerland, assiguor to Griesser A.G., Aadorf, Thurgau, Switzerland Filed Mar. 2, 1964, Ser. No. 348,468 1 Claim. (Cl. 160220) The present invention is a continuation-in-part of my oo-pending United States application Ser. No. 769,162, filed Oct. 23, 1958, now Patent 3,123,131 for Roller Shutter and relates to an improved roller shutter having slats formed of strips of sheet material bent to provide hollow slats having substantially flat sides, a roof-shaped top and -a longitudinal channel or groove along the bottom for cooperation with the roof-shaped top of the next lower slat. The longitudinal edge portions of the strips are bent and folded to interlock at the bottom of the slat, whereas slits are provided at the top .and bottom portions of each slat for the passage of slat carrying tapes provided with means for supporting the slats at the desired vertical spacing.

The present invention also has reference to an improved roller shutter adapted to be made by a method which comprises the steps of first lacquering a plane strip of sheet material, subsequently imparting to said strip of sheet material a continuously extending longitudinal profile by means of profiling rollers and cutting pairs of transversely aligned slits in said strip, transversely folding the profile strip to form a flat tube having an upper roofshaped portion, joining the two longitudinal edge portions of the strip by a folding operation, cutting from the finished tube slats of desired length, and inserting carrier tapes through said slits in the tube slats.

It is, therefore, an important object of the present invention to provide an improved construction of roller shutter manifested by its excellent sturdiness and durability, ease of mobility and rolling movement as well as flexibility.

A further important object of the present invention is to provide an improved roller shutter construction which is easy to assemble from individual hollow slats having passed therethrou-gh improved physical structure of carrier tapes with the resultant roller shutter being highly reliable in operation and possessing easy rolling movement.

Other features, objects and advantages of the invention will become apparent by reference to the following detailed description and drawings in which:

FIGURE 1 is a sectional view of a portion of a roller shutter constructed according to the teachings of the present invention;

FIGURE 2 is a perspective elevational view of a carrier tape employed with the roller shutter according to FIGURE 1; and

FIGURE 3 is a perspective view showing details of a hollow slat of the roller shutter of FIGURE 1, with a portion of the wall thereof broken away to expose physical structure of the carrier tape.

In FIGURES 13 there is illustrated an extremely desirable construction of roller shutter embodying hollow slats. Each of the hollow metal slats 30 includes a roof- .shaped top portion 30a and a channel-shaped bot-tom portion 30b. Slots 31 and 32 are provided in the top and bottom portions 30a and 3% respectively of each hollow slat 30 through which passes the metal foil carrier tapes or hands generally designated by reference numeral 33. At this point it should be mentioned that the slot 31 is somewhat shorter in width than the slot 32, for reasons to be more fully explained shortly hereinafter.

The carrier tapes 33 comprise individual hook or fastening members 34 formed of flexible band material for example, and preferably punched from a single piece.

3,272,256 Patented Sept. 13, 1966 Each individual fastening member 34 is provided at one end with a coupling portion 35 in the form of a flange or clamp arranged at the top of each individual member 34 and adapted to engage with the lower portion 36 of the next adjacent individual member 34 provided with opposed slots or openings 37 for receiving the opposite ends 38 of the coupling portion 35. It will be appreciated that the lower portion 36 of each individual fastening member 34 provided with the slots 37 further incorporates a ledge portion 39 extending out of the plane of the lower portion 36 and merging with a downwardly directed leg 40. This ledge portion 39 serves as a seat for the coupling portion 35 of the adjacent lower individual fastening member 34 when received within the opposed slots 37. It will further be appreciated that the coupling portion 35 p of one individual member can effect a limited movement from their drawn-apart position, as indicated in FIGURE 1, and moved until the upper edge of the coupling portion 35 bears against the inner confines 41 of the slots 37. Here again, in this manner there is obtained the shortening required for closing the roller shutter with the slats 30 overlying in light-proof arrangement, or the lengthening of the carrier tapes 33 necessary for drawing the aforesaid slats away from one another.

It will further be appreciated that each individual fastening member 34 is provided with a flexible or resilient projection-like tab or tongue 42 at its lower end which is adapted to bear against the inner wall 300 of the channel-shaped bottom portion 30b of the associated hollow slat 30 in order to prevent the carrier tape 33 and, in particular, the relevent individual fastening member 34 from moving out of such hollow slat 30. On the other hand, lateral projecting shoulders 43 are provided in the region beneath the coupling portion 35 and serve to bear against the inner face or surface 30d of the roof-shaped top portion 30a to thereby support the associated hollow slat 30. Additionally, it will be recalled the upper slot 31 of each hollow slat 30 is smaller in width than the width between the opposed shoulders 43 to thereby ensure that the individual member 34 when pushed through the larger lower slot 32 cannot move out through the upper slot 31. It will further be appreciated that any downward movement of this individual member 34 out of the lower slot 32 is prevented by the flexible tongue 42 as aforedescribed. Moreover, during assembly of the roller shutter the coupling portion 35 extending out of its associated hollow slat 30 is engaged with the openings 37 of a subsequent individual fiastening member 34, and thereafter the next hollow slat 30 is threaded onto the carrier tape which is being progressively formed during such assembly of the roller shutter. Apart from the advantages of this construction that the individual fastening members 34 can be stamped from a single piece and are retained within the associated hollow slat 30 due to the aforedescribed physical structure, it will further be appreciated that this roller shutter construction enables the latter to be rolledup .at both sides, permits the possibility of combining stationary and movable slats, and the individual fastening nliembers .are movable out of view within the relevent s ats.

It should be understood that the roller shutter disclosed herein, in addition to its great mobility, flexibility and easy rolling movement, is further characterized by its particular sturdiness and durability. Last, but not least, this advantage results from the fact that very small slots in the hollow slats suffice for the reception of the carrier tapes or tape members, and any substantial weakening of the slat structure is thus avoided.

The hollow slatsof the roller shutter are produced as follows: the band used for making the hollow slats first is lacquered, subsequently profiled, then hooked together with its longitudinal edges and finally, after providing the necessary slits, strung up on the carrier tapes.

While there is shown and described a preferred embodiment of the invention it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied .and practised within the scope of the following claim.

What is claimed is:

In a roller shutter, the combination of a plurality of hollow slats of sheet material, flexible carrier tapes on which said slats are suspended, said slats each having a top portion which in cross-section has an upwardly convex wedge shaped cross-section with two oppositely inclined wall portions, and an upwardly concave bottom portion having in cross-section a substantially horizontal middle surface portion and sharply downwardly inclined end portions connecting the bottom portion to the side walls of the hollow slat, the top portion of the next lower slat projecting toward the space within the concave bottom portion of each next upper slat, the slats each being formed by .a strip of sheet material bent to a tube, the longitudinal edges of said stn'p being united at said bottom portion of the slat, the apex of said top portion and the horizontal middle surface of the bottom portion having slots formed therein, and the flexible carrier tapes passing through said slots, said carrier tapes including laterally extending shoulder means for retaining said slats in a substantially horizontal position on said carrier tapes and outwardly and downwardly projecting tongueli-ke projections of material punched out of said carrier tapes at positions spaced longitudinally along the carrier tapes and adjacent at least one of the wall portions of 30 each of the slats connecting the side walls of the slats, said tongue-like projections being resiliently movable toward the carrier tapes to enable the slats to be moved down along the tapes into position thereon and for preventing said carrier tapes from slipping through said slats, said carrier tapes being formed of individual fastening members with each fastening member having at least one of said tongue-like projections and said laterally extending shoulder means, said tongue-like projections each being capable of bearing against said middle surface portion of said concave bottom portion of an associated slat and said laterally extending shoulder means being capable of bearing against said top portion of said associated slat, and each individual fastening member incorporating opposed recesses and a coupling portion, the coupling portion of one individual fastening member being slidably receivable within said opposed recesses of an adjacent individual fastening member.

References Cited by the Examiner UNITED STATES PATENTS 1,848,786 3/1932 Lampert 29-527 1,8 52,9 13 4/ 1932 Bauer 220 1,910,047 5/ 193-3 Passoni 160-220 2,480,711 8/ 1949 (Dalton 29-5 27 FOREIGN PATENTS 204,694 12/1908 Germany.

259,974 -8/ 1928 Italy.

465,683 9/ 1951 Italy.

573,273 2/ 1958 Italy.

595,173 6/ 1959 Italy.

174,568 6/1935 Switzerland.

HARRISON R. iMOSELEY, Primary Examiner.

CHARLES E. OCONNELL, Examiner.

P. M. CA'UN, Assistant Examiner. 

